Nuance has been increasing it's dominance in voice directed apps on the iOS platform the past few months with the last offering allowing you to use your iPhone/iPod Touch as a microphone for their desktop based Dragon software.
Well today they just moved the bar much higher with their Dragon G0! app (iTunes link) that allows you to use your iPhone much more intuitively by voice.
Navigate Facebook, launch a specific station on Pandora or get driving directions to a new destination - the options are endless.
You can see more details at the Press Release and pick it up for free at iTunes.